The US Army Corps of Engineers will not grant permission for the Dakota Access Pipeline to cross Lake Oahe, the hotspot of massive protests of water protectors, the Standing Rock Sioux Tribe said in a statement, adding that alternative routes are now being studied.

"The Department of the Army will not approve an easement that would allow the proposed Dakota Access Pipeline to cross under Lake Oahe in North Dakota," said a statement on the US Army website, citing the Assistant Secretary for Civil Works, Jo-Ellen Darcy.

According to Darcy, it was “clear” they needed to address concerns of tribal leaders who expressed concerns over the potential environmental impact of the Dakota Access Pipeline, and “the best way to complete that work responsibly and expeditiously is to explore alternate routes for the pipeline crossing.”

“The consideration of alternative routes would be best accomplished through an Environmental Impact Statement with full public input and analysis,” the Army statement said.

Standing Rock Sioux chairman Dave Archambault II has issued a statement expressing his gratitude to the Obama administration for enabling the “historic decision” to re-reroute the pipeline.

“We wholeheartedly support the decision of the administration and commend with the utmost gratitude the courage it took on the part of President Obama, the Army Corps, the Department of Justice and the Department of the Interior to take steps to correct the course of history and to do the right thing,” he wrote.

The news is a massive win for the Sioux tribe that established the protest camp at the site in April and has gained huge support in recent weeks.

The pipeline was intended to pass through North Dakota's Lake Oahe, which is a burial site sacred to the Standing Rock Sioux. The tribe voiced concerns the pipeline would threaten the community’s drinking water and would also damage sites of sacred significance.

North Dakota Governor Jack Dalrymple reacted to the news of the changed route in a statement, calling the decision ‘‘a serious mistake’’ that “prolongs the serious problems” that law enforcement faces, as well as what he described as the dangerous situation experienced by those camping in cold winter conditions.

US Attorney General Loretta Lynch said that the Department of Justice will continue to monitor the protest in North Dakota in the coming days, and is ready to ‘‘provide resources’’ for those who ‘‘can play a constructive role in easing tensions.’’

Standing Rock Sioux tribe also expressed its wish to heal the relationship with police following tensions and clashes during the standoff. While protests have been largely peaceful, confrontations with police have led to violent clashes in recent weeks.

Stunning victory at StandingRock! When's the last time the federal gov't was defeated by the Native peoples? Inspiration for what's ahead...

Some 26 activists were injured in a November 20 confrontation when police fired water cannon in below-freezing temperatures. Rubber bullets and tear gas were also reportedly used against the water protectors on site.

Around 564 people were arrested during the protests, according to the Morton County Sheriff's Department.

The Army Corps of Engineers previously threatened that the camp would be closed on December 5, ostensibly to protect the public amid violent confrontations between protesters and law enforcement agencies.

Brenda White Bull, a veteran and descendant of Chief Sitting Bull, explained the significance of the site, telling the authorities that Native Americans’ relatives and leaders are buried on Turtle Hill.

“Destroying our sacred burial sites is like someone going through Arlington National Cemetery and digging up all those grave sites. We would never desecrate veterans’ grave sites, out of respect,” she told law enforcement.

“This movement has never been about North Dakota law enforcement or about attacking the police and we have never done that. The only times there have been confrontation is when they confront us and forcibly remove us from unceded treaty lands by using war weapons against unarmed Water Protectors,” Kandi Mossett of the Indigenous Environmental Network said, referring to the 1851 Treaty of Ft. Laramie that refers to the area as sovereign land under the control of the Oceti Sakowin (Seven Council Fires of the Sioux).

Morton County sheriff Kyle Kirchmeier on Sunday defended tactics used against the water protectors, telling Reuters he hoped the rallies would be peaceful. Referring to the water cannon incident, he said it was the protesters who got in the way and “all you had to do was back up and you wouldn’t get wet.”

The sheriff added they “don’t care” which way the easement decision on the pipeline crossing is made, adding that it is the law enforcement’s job to enforce it.